Carton with integral lock tab and slot closures



y 3, 1969 J. c. MCKINNEY 3,443,740

CARTON WITH INTEGRAL LOCK TAB AND SLOT CLOSURES Original Filed July 6.1965 Sheet 23 F .I 2s A 2 ,20 5

25 Q Z4 L L .f i7 15 (2: '15,! l4 8 //Z /1 0 L L0 19 I T I I? p? i I '6IP24 I MY Ll a 1!,

II I i I H 12 [NVENTQR JAMES C. Mc KINNEY l" ,1

Ar -rvs.

J. C. M KINNEY May 13, 1969 CARTON WITH INTEGRAL LOCK TAB AND SLOTCLOSURES Original Filed July 6, 1965 lm/emon James C. MCKINNEY J'fi ZPAM,MM$ 4ZQ A-rrvs,

May 13, 1969 J. c. M KINNEY 3,443,740

CARTON WITH INTEGRAL LOCK TAB AND SLOT CLOSURES Original Filed July 6,1965 Sheet 5 of3 United States Patent 3,443,740 CARTON WITH INTEGRALLOCK TAB AND SLOT CLOSURES James C. McKinney, Taylors, S.C., assignor toKellogg Company, Battle Creek, Mich., a corporation of DelawareContinuation of application Ser. No. 469,752, July 6,

1965. This application May 26, 1966, Ser. No. 553,005

Int. Cl. B65d /10 US. Cl. 229-39 8 Claims ABSTRACT OF THE DISCLOSURE Acarton comprising side walls, end walls, and bottom and top closureflaps hinged to said walls, said top closure flaps comprising a pair ofdust flaps hinged to said end walls and a pair of elongated upper flapshinged to said side walls, a first one of said elongated flaps beingadapted to overlie the other of said elongated flaps and including anopposed pair of end lock tabs hinged thereto for reception incomplementary slits, said slits each comprising a first portion formedin said dust flaps closely adjacent and parallel to their hinge lines ofa length substantially equal to that of the hinge line of said tab, afree end portion of each lock tab being shaped to extend beyond said tabhinge line and adapted to be received in a second slit portion extendingfrom and inclined to said parallel slit portion and to underlie saiddust flap at an unslit portion thereof, the total length of each of saidstraight and inclined slit portions being substantially equal to thetotal length of the hinged and free end portions of each of said locktabs.

This application is a continuation of Ser. No. 469,752, filed July 6,1965, now abandoned.

This invention relates to improvements in cartons and particularly torecloseable cartons.

It has heretofore been known to provide cartons, particularly in thecereal packaging trade, with top closures comprising a pair of end ordust flaps folded down first, an elongated side flap folded thereoverand lightly adhered to the dust flaps, and an uppermost elongated sideflap lightly adhered to the first mentioned elongated side flap. Also asheretofore conventional, the lower one of the aforementioned two sideflaps was provided with a slit or slot in a depressible portion and theother or uppermost side flap was provided with a tongue adapted to bereceived in the slot of the first elongated flap so as to providereclosure means after the adhesive seals have been broken.

It is an object of the present invention to provide a recloseable cartonhaving top closure flaps as aforesaid except that the adhesion betweenthe flaps as aforesaid is dispensed with and interlocking means areprovlded in lieu of adhesive whereby the carton can be readily openedwithout necessity for special instruments, and whereby the carton may bereadily repeatedly closed and reopened in a simple and efficient manner.

Other objects and advantages of the present invention,

its details of construction, arrangement of parts and economies thereof,will be apparent from a consideration of the following specification andaccompanying drawings wherein:

FIG. 1 is a blank development of one form of the carton of the presentinvention.

FIG. 2 is a perspective view of the carton for-med from the blank ofFIG. 1, which is but partially closed.

FIG. 3 is a view similar to that of FIG. 2 but with the top flaps of thecarton all in closed or locked position.

FIG. 4 is a fragmentary side elevational view of the closed carton topshown in FIG. 3.

FIG. 5 is a fragmentary elevational view of the top of the closed cartonshown in FIG. 3.

FIG. 6 is a section on the line 66 of FIG. 5.

FIG. 7 is a fragmentary blank development of a modified form of cartonconstruction.

FIG. 8 is a perspective view of a carton formed from the blank of FIG.7, in partially closed condition.

FIG. 9 is a similar perspective view of the carton of FIG. 8 in fullyclosed position.

FIG. 10 is a fragmentary plan view of the carton blank showing anothermodified form of construction.

FIG. 11 is a fragmentary perspective view of a partially closed cartonof the blank shown in FIG. 10.

FIG. 12 is a perspective view progressive to that of FIG. 11 showing thecarton top fully closed.

FIG. 13 is a fragmentary section on line 13-13 of FIG. 12.

FIG. 14 is a fragmentary section on line 1414 of FIG. 13.

Referring to FIGS. 1 to 6, the reference numerals 10, 10 indicate thesides of the carton and 11, 11 the ends thereof. It will be understoodthat for the purpose of facilitating explanation herein, while two ofthe wider walls of the carton have been designated as sides and the twonarrower walls of the carton have been designated as ends. Generally,cartons of the class here indicated such as are used for the packagingof cereals have tWo relatively wider walls and two relatively narrowerwalls.

Attached to the side of one of the walls 10 is a flap 12 which isadhesively united to the outermost panel 11 to form a rectangular cartonas shown in FIG. 2. For forming a closure, the top of the carton isprovided with a pair of dust flaps 13, 13 hingedly engaged at 14 to thefiaps 11. Each of these dust flaps 13, 13 is provided with a slit 15parallel to the hinge line 14 and closely adjacent thereto. These slits15 continue on with inclined portions 16 which extend into the end walls11 in a direction towards side wall 10. conventionally, these dust flaps13 are folded down first. There is thereafter folded over against thedust flaps the elongated first flap 17 hinged to one of the panels 10 asat 18, this closure flap 17 being provided medially with a slit 19having arcuate end portions leaving a depressible portion 20. Theopposing side wall 10 has hinged thereto at 21 the uppermost elongatedclosure flap 22 which is provided medially with a tongue 23 adapted tobe received in the slit 19 whereby to hold the closure flaps 17 and 22in interengagement.

The uppermost closure flap 22 is further provided at its opposed endswith the lock tabs 24, 24 hinged thereto at 25, the outer terminal ofthe tab being spaced as at 26 from the flap 22.

Thus after the dust flaps 13 are folded down and the flap 17 foldedthereover, the flap 22 is then folded down next and its tabs 24 insertedin the slits 15 in a manner whereby the outermost end of the tabs 24project into the inclined slit end portions 16. The length of thestraight slit portions 15 is substantially equal to the length of thetabs 24 at their hinge lines with the flaps 22, and the total length ofthe slit portions 15 and 16 is substantially equal to the total lengthof the tabs 24, that is, the length of the line 25 at which they arehinged to the flaps 22 plus the extension beyond at the cut-out portion26 to the outer free edge of the lock tab portion.

When the flap 22 is thus closed down as shown in FIG. 2, the tabs 24first enter the straight slit portions 15 and thereafter enter theinclined slit portions 16 whereat the free ends of the tabs snap or flexto a planar position and edgewise lodge under dust flaps 13 adjacent totheir hinge lines 14 at the end walls 11, to provide a secure lockresistant against upward accidental withdrawal of the flaps 22. At thisposition, the tongue 23 can be inserted in the slit 19 as an interlockaid. This interlock serves a secondary purpose in that upon repeatedopening of the top closure flaps there may be some partial rupture ofthe tabs 24 or the areas adjacent to the slit portions 15 and 16.However, initially there is a very firm closure and which may be readilyopened without necessity for use of lines or spots of adhesive, andreclosure may be readily efifected in a secure manner adequate forcontinued use of the carton contents until exhausted.

Although I have shown one tab 24 at each of the lateral edges of theflap 22, it will be understood that more than one may be employedparticularly on large size cartons, and in such event a plurality ofslits formed of components 15 and 16 can be employed partially in theflap 17 and partially in the end walls 11.

It will also be understood that although I have shown one tongue 23 andslit 19, the flaps 17 and 22 may be provided with more than one pair oftongue and slot interengagement means.

Although I have shown in FIG. 1 bottom closure flaps 13', 13' and 22,17', which can be adhesively secured in hitherto conventional manner, inthe alternative the bottom of the carton can be formed with flaps, tabsand slits as previously explained with respect to the top of the carton.

Referring specifically to the modified form of construction shown inFIG. 7, this construction and arrangement is essentially the same asthat described with respect to FIGS. 1 to 5, with the followingmodification: the slit components 15 which are parallel to the hingelines 14 between the end walls 11 and the dust flaps 13, terminate ininclined portions 16' which extend into the dust fiaps 13 instead ofinto the end walls 11.

The tabs 24 which are hinged at 25 to the uppermost closure flaps 22 canalso be separated from the flaps 22 by a slit 26 in lieu of the cut-outportion 26 previously described but which results in the sameinterlocking eflect. That is, when the tabs 24 are inserted in theseparate slit portions 15 the outermost end of the tabs which areseparated at the line 26' enter the inclined slit portions 16' and thensnap or straighten out to lodge beneath the unslit portion of the dustflap 13 to provide the previously indicated firm interlock.

Referring to the modified form of construction shown in FIGS. to 14,this construction and arrangement is also essentially the same as thatdescribed with respect to the previous figures, with the followingmodifications:

One end of lock tabs 24 are separated from the flaps 22 at slits orcut-out portions 27, 27 leaving an oppositely projecting pair of tongueportions 28, 28 and thus forming an opposed pair of tab portions. Eachtab 24 and its tongues 28, 28 are received in a slit formed in a dustflap 13 and lying parallel to its fold line 14.

In lieu of a single inclined extension as shown in the previous forms,the slit 15 in this case has a pair of inclined slit portions '29, 29extending from the slit 15 into a Wall 11, the inclined slit portions29, 29 being inclined in opposite directions. (Although not shown, oneof the inclined slit portions 29, 29 can extend upwardly and outwardlylying wholly in flap 13 similar to inclined slit portion 16' shown inFIG. 7). As in the previous forms, the total width of the tab 24 fromthe outermost ends of its tongues 28, 28 is equal to the total width ofthe slit 15 and its extensions 29, 29, and likewise the width of thetabs 24 at the fold lines 25 is equal to the width of the straight slitportion 15.

Although I have shown and described preferred embodiments of myinvention, it will be understood by those skilled in the art thatchanges may be made in the details thereof without departing from thescope as comprehended by the following claims.

I claim:

-1. A carton comprising side walls, end Walls, and bottom and topclosure flaps hinged to said walls, said top closureflaps comprising apair of dust flaps hinged to said end Walls and a pair of elongatedupper flaps hinged to said side walls, a first one of said elongatedflaps being adapted to overlie the other of said elongated flaps andincluding an opposed pair of end lock tabs hinged thereto for receptionin complementary slits, said slits each comprising a first portionformed in said dust flaps closely adjacent and parallel to their hingelines of a length substantially equal to that of the hinge line of saidtab, a free end portion of each lock tab being shaped to extend beyondsaid tab hinge line and adapted to be received in a second slit portionextending from and inclined to said parallel slit portion and tounderlie said dust flap at an unslit portion thereof, the total lengthof each of said straight and inclined slit portions being substantiallyequal to the total length of the hinged and free end portions of each ofsaid lock tabs.

2. The carton of claim .1 wherein the inclined slit portions are formedin the dust flaps.

3. The carton of claim 1 wherein the inclined siit portions extend intothe end walls.

4. The carton of claim 1 wherein the lock tabs have a single spacedterminal end portion.

5. The carton of claim 1 wherein the lock tabs have an opposed pair ofspaced terminal end portions.

6. The carton of claim 1 wherein a first one of said elongated flapscomprises tongue means disposed between said end walls adapted forreception in slot means formed in the other of said elongated flaps.

7. A carton blank cut and scored to define side walls, end walls, andbottom and top closure flaps hinged to said walls adapted to be set inrectangular form, said top closure flaps comprising a pair of dust flapshinged to said end walls and a pair of elongated upper flaps hinged tosaid side walls, a first one of said elongated flaps comprising tonguemeans adapted to be disposed between the end walls for reception in slotmeans formed in the other of said elongated flaps and including anopposed pair of end lock tabs in part hinged thereto and terminating ina free end portion for reception in complementary slits, said slits eachcomprising a first portion formed in said dust flaps closely adjacentand parallel to their hinge lines of a length substantially equal tothat of the hinge line of said tab, a free end of each lock tab beingshaped to extend beyond said tab hinge line and adapted to be receivedin a second slit portion extending from and inclined to said parallelslit portion and to underlie said dust flap at an unslit portionthereof, the total length of each of said straight and inclined slitportions being substantially equal to the total length of the hinged andfree end portions of each of said lock tabs.

8. A carton comprising side walls, end walls, and bottom and top closureflaps hinged to said walls, said top closure flaps comprising a pair ofdust flaps hinged to said end walls and a pair of elongated upper flapshinged to said side walls, a first one of said elongated flaps overlyingthe other of said elongated flaps and including an opposed pair of endlock tabs hinged thereto and disposed in complementary slits, said slitseach comprising a first portion formed in said dust flaps closelyadjacent and parallel to their hinge lines of a length substantiallyequal to that of the hinge line of said tab, a free end of each lock tabbeing shaped to extend beyond said tab hinge line and received in asecond slit portion extending from an inclined to said parallel slitportion and underlying said dust flap at an unslit portion thereof, thetotal length of each of said straight and inclined portions beingsubstantially equal to the total length of the hinged and free endportions of each of said lock tabs.

References Cited UNITED STATES PATENTS Cameron 229--38 Van Horne 22939Buttery 22-9-39 X Buttery et al. 229--39 Andrews et al 22'939 X Lizan etal 229-39 X Arneson 229-35 Paige 22-9-35 Crisafulli 229--27 DAVIS T.MOORHEAD, Primary Examiner.

